Disk harrow



R. H. MITCHELL msx mumow April 1, 1941.

Original Filed May 5, 1936 2 Sheets-Sheet l FIG'I INVENTOR QoLLu: HMU'CHELL April 1941- R. H. MITCHELL 2.237.009

D I SK HAHROW Original Filed May 5, 1956 2 Sheets-Sheet 2 INVENTORIZOLLIE H MITCHELL A VORNEY Patented Apr. 1, 1941 DISK HARROW Rollie 11.Mitchell, Huntington Park, CaliL, as-

signor to Killefer Manufacturing Corporation, Los Angeies, Calm, acorporation of California Original application May 5, 1936, Serial No.77,974, now Patent No. 2,169,471, dated August 1939, Serial No. 284,828

18 Claims.

The present invention relates to disk harrows and more particularly to acontrol mechanism for controlling the operation of an offset tandem diskharrow such as is used for cultivating the ground in orchards. Thisapplication is a division of a. co-pending application, Serial No.77,974, filedMay 5, 1936, now Patent No. 2,169,471, issued August 15,1939, and has for its principal object the provision of lockingmechanism for locking the two gangs of an offset disk harrow relative toeach other and to the hitch in a predetermined angled position duringnormal operation, but which mechanism is automatically unlocked when thetractor is turned in the direction in which the disk gangs are spreadapart, permitting the gangs to be moved out of their working angle, thusfacilitating making the turn. A further and more specific object relatesto the provision of an offset auxiliary draft connection between thetractor and the harrow, which is connected to the locking mechanism andis pulled forward during a turn of the tractor, first unlocking thelocking mechanism and then transmitting draft force from the tractor tothe harrow which tends to swing the gangs out of their working angle. Afurther object relates to the provision of a novel locking mechanism forthe purposes mentioned above, employing toggle links which can be movedinto and out of dead center locking position to lock and unlock thegangs.

These and other objects and advantages will be made apparent by aconsideration of thefollowing description, reference being had to thedrawings appended hereto, in which Figure 1 is a plan view of an, offsetdisk harrow shown in right-hand offset working position and embodyingthe principles of my invention; and

Figure 2 is a plan view of the harrow shown in .a right-hand turn.

Referring now to the drawings, the harrow comprises a front disk gang 5and a rear disk gang 6, each of the gangs comprising a structural frame1, 8, and a plurality of ground working disks 9 assembled in spacedrelation on a gang bolt l0 journaled for rotation on each of the gangframes. The frames I, 8 are connected together for angling movement on ahorizontal plane by a-pair of links H, pivoted at laterally preventingrelative sliding movement in either Divided and this application July17,

draft means represented by the draft member 20, from which draft forceis transmitted by a hitch 2|, pivotally connected at 22 to the tractor20 and connected to both gangs in a manner to be described. The hitchcomprises a pair of hitch bars 23, 24, pivoted together at 25. The hitchbar 24 is adjustable in length to adjust the amount of offset of theharrow relative to the tractor in well known manner, and is connected bya universal joint 26' to the right front corner of the front gang frame.A transverse lever or bar 21 is pivoted intermediate of its ends at 28to a bracket 29, fixed to the front gang frame 1. The hitch bar 23 isswingably connected to the left end of the lever 21 by a universal joint30. The opposite end of the lever 21 is swingably connected to an anglecontrol bar 3|, which extends rearwardly and is pivoted at 32 to theright side of the rear gang frame 8.

The harrow gangs are pulled into working angle from a parallel relationby driving the tractor forwardly, by virtue of the draft force'exertedforwardly upon the right front corner of the forward gangthrough the hitch bar 24, and also exerted through the hitch bar 23 tothe lever 21, resulting in a rearward thrust through the angle controlbar 3| to the right end of the rear gang frame 8.

The gangs can be locked together in any of several working angles bymeans of a locking device 35, comprising a pair of toggle links 36, 31,pivotally connected together at 38 in serial relation, one of the links31 being pivoted to the front of the forward gang frame 1 at a point 39near the left end thereof, the other link 36 being connected to thetransverse lever 21, on the left side of the pivot 28, by means of anadjustable angle selector latch 40. The latch 40 comprises a tubularcage 4| adapted to slidably receive the link 36, and is pivoted at 42 onthe lever 21. A latch dog 43 is pivoted at 44 on the cage 4| and isadapted to engage the teeth of a rack 45, formed on the link 36.Suitable spring means (not shown) are provided to normally hold the dog43 in locking engagement with the rack 45,

, direction.

The latch dog is controlled from the tractor operators station by meansof a flexible control member, such as arope 46, connected to an arm 41fixed to the dog. When the rope is pulled, the dog is swung out ofengagement with the rack 45, after which the gangs can be pulled intoworking angle by pulling the harrow forward, or straightened into aparallel or transport position by backing the tractor against the hitch.When the desired position is attained, the gangs can be locked thereinby releasing the rope 46, allowing the dog 43 to reengage the rack 45;

The gangs are. then locked in position against movement in eitherdirection, the links being resistant against a compression force thereonby virtue of the dead center locked relation in which the links arenormally disposed; that is to say, the pivot 33 between the links isaligned with the points 39, 42 at which the opposite ends of the linksare connected to the lever 21 and gang frame 1, respectively. If sodesired, the-pivot 38 may be even slightly to the left (as viewed in thedrawings) of a straight line connecting the pivots 39, 42, therebylocking the links more positively. The links are prevented from bucklingin one direction by an extension arm 50 on one of the links 36, having astop which engages the other link 31 when the center pivot 38 is on orslightly over dead center. The links are free to swing or buckle in theopposite direction, however, in order to release the gangs fromangularly locked position when it is desired to make a right turn.

To unlock the toggle device, a bell crank or arm 52 is provided on therear link 31, and by a forward pull on the bell crank, the link 31-, andhence the pivot 38 is swung toward the right until the locking effect ofthe toggle is overcome. A spring 53 is provided to normally hold thetoggle links in locked position, and is connected between the bell crank52 and a member of the front gang frame 1. The crank 52 is controlled bya member 54, connected thereto and extending forwardly to the tractor,the front end of the member being connected to a laterally extending arm55 at a point 56 ofiset laterally from the hitch pivot 22. The arm 55 isfixed rigidly to the draft means 20 so that as the latter is turned tothe right, as illustrated in Figure 2, the member 54 is pulledforwardly, thereby-pulling the arm 52 forwardly about the pivot.39,first breaking the toggle lock and then exerting a draft force throughthe arm 52 upon the left end of the front gang frame 1, tending to pullthe latter.

forwardly, with the result that the gangsarej pulled out of theirworking angle into parallelrelation, or even beyond the latter intooppositely angled relation, thus facilitating the right turn. I

As soon as the draft means is straightened into forward movement in thenew direction, the draft force is relieved from the auxiliary draftmember 54, whereupon the gangs are pulled back I do not intend myinvention to be limited to ters Patent is set forth in thefollowingclaims.

I claim:

1. A disk harrow comprising a front disk gang, a rear disk gang, meansinterconnecting said gangs providing for relative angling movement ofsaid gangs in a horizontal plane, hitch means connecting said front gangto a suitable draft means, a draft connection between said hitch meansand said rear gang, means for locking said gangs in a predeterminedposition relative to each other, said locking means including a pair 01toggle links connected between said gangs and disposed in dead centerlocking relation when the gangs are in said predetermined position, andcontrol means by which said links can be moved out of said dead centerlocking relation to permit said gangs to be moved out of saidpredetermined position.

2. A disk harrow comprising a pair of disk gangs swingably connectedtogether for angling movement in a horizontal plane, hitch meansconnected to one of said gangs and adapted to be connected to a tractor,an angle control bar connected between said hitch means and the other ofsaid gangs, inelans for locking said gangs in angled position co prisinga pair of serially connected toggle links, one of said links beingconnectedto one of said gangs and the other link being connected withthe other of said gangs,

said links being normally disposed in substanbe connected to a tractor,means for locking said gangs in angled position comprising a pair ofserially connected toggle links, one of said links being connected toone of said gangs and the other link being connected with the other ofsaid gangs, said-links being normally disposed in substantially deadcenter locked position to restrain said gangs from moving out of saidangled position, spring means for yieldably holding said links in lockedposition, and an auxiliary draft member adapted to be attached to saidtractor and connected with said links for moving the latter out of saiddead center position to permit said gangs to bemoved out of said angledposiserially connected toggle links, one of said links the precisedetails shown and described in this embodiment. Other locations of thetoggle links will now be obvious to those skilled in the art, in whichthe gangs can be locked together in angled position and in which anoffset draft connection will be effective to release the toggle lock- 7ing device and then apply a force tending to swing the gangs out ofangled position.

What I desire to protect by United States Letbeing connected to one ofsaid gangs and the other link being connected with the other of saidgangs, said links being normally disposed in substantially dead centerlocked position to restrain said gangs from moving out of said angledposition, spring means for yieldably holding said links in lockedposition, and a flexible control member connected with one of said linksand extending forwardly to the tractor, said links being movable out ofsaid locked position responsive .thereby permitting said to a forwardpull on said control member and gangs to be moved out of said angledposition.

5. In a disk harrow comprising a pair of disk gangs swingably connectedtogether for angling movement in a horizontal plane and flexible hitchmeans connected to both gangs and adapted to be connected to a tractor,means. for locking said gangs in angled position comprising a pair ofserially connected toggle links, one of said links being connected toone of said gangs and the other link being connected with the other ofsaid gangs, said links being normally disposed in substantially deadcenter locked position to restrain said gangs from moving out of saidangled position, spring means for yieldably holding said links in lockedposition, a bell crank connected to one of said links, and a flexiblecontrol member attached to said bell crank and extending forwardly tothe tractor, said links being movable out of said locked positionresponsive to a forward pull on said control member and therebypermitting said gangs to be moved out of said angled position.

6. In a disk harrow comprising front and rear disk gangs swingablyconnected together for angling movement in a horizontal plane, hitchmeans connected to said front gang and adapted to be connected to atractor, an angle control bar connected between said hitch means and theother of said gangs, means for selectively locking said gangs in any ofa plurality of angled positions relative to each other comprising a pairof serially connected toggle links, one of said links being connected toone of said gangs and adjustable means for selectively connecting theother of said links with the other of said gang in any of said angledpositions of the gangs, said links being normally disposed in deadcenter locked position to restrain said gangs from moving out of saidangled position, and a control member connected with said links formoving the latter out of said dead center position to permit said gangsto be moved out of said angled position.

7. In a disk harrow comprising front and rear disk gangs swingablyconnected together for angling movement in a horizontal plane andflexible hitch means connected to said front gang and adapted to beconnected to a tractor, an angle control bar connected between saidhitch means and said rear gang, means for selectively locking said gangsin any of a plurality of angled positions relative to each othercomprising a pair of serially connected toggle links, one of said linksbeing connected to one of said gangs and means including an adjustablelatch for selectively connecting the other of said links with the otherof said gangs in any of said angled positions of the gangs, said latchbeing provided with a control member under control of the tractoroperator, said links being adapted to normally restrain said gangs frommoving out of angled position, and a control member connected with 7said links for unlocking the latterto permit the gangs to be moved outof said angled position.

8. In a disk harrow comprising front and rear disc gangs swingablyconnected together for angling movement in a horizontal plane and hitchmeans connected to both gang and movable relative thereto and adapted tobe connected to a tractor, means for locking said gangs in angledposition comprising a pair of serially connected toggle links, one ofsaid links being connected to one of said gangs and the other link beingconnected to said hitch means, said links being normally disposed insubstantially dead center position to lock said gangs and said hitchmeans in a rigid unitary structure, and a control prising a pair ofserially connected toggle links,

member connected with said links for moving the latter out of said deadcenter position to permit said gangs to be moved out of said angledposition,

9. In a disk harrow comprising front and rear disk gangs swingablyconnected together for angling movement in a horizontal plane andflexible hitch means connected to both gangs and adapted to be connectedto a tractor, means for selectively locking said gangs in any of aplurality of angled positions relative to each other comone of saidlinks being connected to one of said gangs and a latch device mounted onsaid hitch means and adapted to slidably receive the other of said linkand to engage the latter in any of said angled positions of said gangs,said links being normally disposed in a substantially dead centerposition to lock said gangs and said hitch means together to restrainsaid gang and said hitch member from relative angling movement,

and a control member connected with said links for moving the latter outof said dead center position to permit said gangs to be moved out ofsaid angled position.

10. In a disk harrow comprising a front disk gang, a rear disk gang,means swingably connecting said gangs together for angling movement in ahorizontal plane, a transversely disposed lever pivotally mounted on oneof said gangs, a connection from said lever to the other of said gangs,and a tractor hitch connected to said one gang and said lever, a pair ofserially connected toggle links connected between said one gang and saidlever and normally disposed in substantially dead center relation torestrain said gangs from moving relative to each other and to saidhitch, and control means connected with said links for moving the latterout of said dead center relation to permit said gangs to be movedangularly.

11. In a disk harrow comprising a front disk gang, a rear disk gang,means swingably connecting said gangs together for angling move" ment ina horizontal plane,.a transversely disposed lever pivotally mounted onone of said gangs, a connection from said lever to the other of saidgangs, and a tractor hitch connected to said one gang and said lever, apair of serially connected toggle links, one of said links beingconnected to one of said gangs and means includ ing an adjustable latchfor selectively connecting the other of said links with said lever inany of a plurality of angled positions of said gangs, said links beingnormally disposed in substantially dead center relation, and controlmeans for moving the latter out of said dead center relation.

12. In a disk harrow comprising a front disk gang, a rear disk gang,means interconnecting said gangs providing for relative angling movementof said gangs in a horizontal plane, and hitch means for connecting saidgangs to a suitable draft means, means for locking said gangs in apredetermined position relative to each other, said locking meansincluding a pair of toggle links connected between said gangs anddisposed in dead center locking relation when the gangs are in. saidpredetermined position, and control means by which said links can bemoved out of said dead center locking relation to permit said gangs tobe moved out of said predetermined position, said 'control meanscomprising a con-- nection of said hitch means thereto, and adapted tobe actuated when the draft means is turned.

. 13, In a disk harrow comprising a pair of disk gangs swingablyconnected together for angling movement in a horizontal plane andflexible hitch means connected to both gangs and adapted to be connectedto a tractor, means for locking said gangs in angled position comprisinga pair of serially connectedtoggle links, one of said links beingconnected to one of saidgangs and the other link being connected withthe other of, said gangs, said links being normally disposed insubstantially dead center locked position to restrain said gangs frommoving out of said angled position, and a control member connected withsaid links and adapted to be fastened to the tractor at a point offsetfrom the pointof connection of said hitch means thereto, whereby saidlinks are moved out of said dead center relation by a force applied tosaid control member as the tractor is turned in one direction, therebyreleasing said gangs for movement out of said angled position.

14. In a disk harrow comprising a pair of disk gangs swingably connectedtogether for angling movement in a horizontal plane and flexible hitchmeans connected to both gangs and adapted to be connected-to a tractor,means for locking said gangs in angled position comprising a pair ofserially connected toggle links, one of said links being connected toone of said gangs and the other link being connected with the other ofsaid gangs, said links being normally disposed in substantially deadcenter locked position to restrain said gangs from moving out of saidangled position, and an auxiliary draft member connected with said linksand adapted to be fastened to the tractor at a point offset from thepoint of connection of said hitch means thereto, said auxiliary draftmember being pulled forwardly by virtue of its ofiset connection withthe tractor as the latter is turned in one direction, thereby firstmoving said links out of said dead center position and transmitting adraft force from the tractor tending to swing said gangs out of saidangled position. 15. In a disk harrow comprising a pair of disk gangsswingably connected together for angling movement in a horizontal planeand flexible hitch means connected to both gangs and adapted to beconnected to a tractor, means for locking said -gangs in angled positioncomprising a pair of to, whereby a forward pull on said control memberis effected by turning the tractor in one direction, said links beingmovable out of said locked position responsive to such forward pull,thereby permitting said gangs to be moved out of said angled position.

16. In a disk harrow comprising a pair of disk gangs swingably connectedtogether for angling movement in a'horizontal plane and flexible hitchmeans connected to both gangs and adapted to be connected to a tractor,means for locking said gangs in angled position comprising a pair ofserially connected toggle links, one of said links being connected toone of said gangs and the other link being connected with the other ofsaid gangs, said links being normally disposed in substantially deadcenter locked position to restrain said gangs from moving out of saidangled positionfitbell crank connected to one of said links, and aflexible control member attached to said bell crank and extendingforwardly to a point of connection with the tractor offset laterallyfrom the point of connection of said hitch means thereto, whereby aforward pull on said control member is effected by turning the tractorin one direction, said links being movable out of said locked positionresponsive to such forward pull. thereby permitting said gangs to bemoved out of said. angled position, said forward pull then beingtransmitted through said bell crank to one of said gangs effectively toswing the gangs out of said angled position.

17. In a disk harrow comprising front and rear disk gangs swingablyconnected together for angling movement in a horizontal plane andflexible hitch means connected to both gangs and adapted to be connectedto a tractor, means for selectively locking said gangs in any of aplurality of angled positions relative to each other comprising a pairof serially connected toggle links, one of said links being connected toone of said gangs and means including an adjustable latch forselectively connecting the other of said links with the other of saidgangs in any of said angled positions of the gangs, said latch beingprovided with a control member under control of the tractor operator,said links being adapted to normally restrain said gangs from moving outof angled position, and a control member connected with said links andadapted to be fastened to the tractor at a point offset from the pointof connec-- tion of 'said hitch means thereto, whereby said links aremoved out of said dead center relation by a force applied to saidcontrol member as the tractor is turned in one direction, therebyreleasing said gangs for movement out of said angled position.

18. In a disk harrow comprising front and rear disk gangs swingablyconnected together for angling movement in a horizontal plane andflexible hitch means connected to both gangs and adapted to be connectedto a tractor, means for selectively locking said gangs in any of aplurality of angled positions relative to each other comprising a pairof serially connected toggle links, one of said links being connected toone of said gangs and means including an adjustable latch forselectively connecting the other of said links with the other of saidgangs in any of said angled positions of the gangs, said latch beingprovided with acontrol member under control of the tractor operator,said links being adapted to normally restrain said gangs from moving outof angled position, and an auxiliary draft member connected with saidlinks and adapted to be fastened to the tractor at a point offset fromthe point of connection of said hitch means thereto,

, said auxiliary draft member being pulled forwardly by virtue of itsoffset connection with the tractor as the latter is turned in onedirection.

thereby first moving said links out of said dead center position andtransmitting a draft force from the tractor tending to swing said gangsout of said angled position.

ROLLIE H. MITCHELL.

